Metal Hyperaccumulator Plants and Environmental Pollution

Abstract

During evolutionary history of life on Earth, different life forms have undergone harsh environmental conditions. Plants have evolved multiple life forms and some of the specialist pioneer plants have the ability to colonize in hostile environmental conditions. Some plant taxa have the ability to accumulate high concentrations of potentially toxic trace elements (Ni, Zn, Cd, Se, As, Mn, Co, Cu, Pb, Sb, Tl) in their biomass. In some of these, taxa concentration of trace elements exceeds the concentration of macronutrients (e.g., Ca, K). Furthermore, metal hyperaccumulation is strongly associated with enhanced ability of these plants to detoxify the accumulated metal in the tissues. Such hyperaccumulation property has been reported in a total of approximately 500 Angiosperm species. This ability of the plants can be used for pollutant stabilization, extraction, degradation, or volatilization. The present chapter discusses heavy metals uptake mechanisms by plants and the potential of phytoremediation technique on treating heavy metal contaminated sides.